I interviewed Marion Nestle, co-author of Why Calories Count recently, and you can find an edited transcript of our conversation on the My Net Diary blog. The book presents a very thorough pictures of the history of nutrition science, and how our obsession with calories began. We’re so used to being bombarded by calorie information these days, it’s hard to imagine there was a time that people didn’t actually understand that food provided the caloric energy we use to stay alive. Anyone who wants an in depth understanding of calories, weight management and obesity will find it in this book. But this is no diet book. If anything, Nestle’s diet advice is extremely simple: weigh yourself. If you find your clothes are getting tight, or your weight is creeping up, cut back on food. No special meal plans or recipes or supplements or food combinations. Just cut back.
Nestle places a great deal of confidence in the power of public policy to solve the obesity problem, as a way to limit available calories (see: Mayor Bloomberg’s soft drink restrictions), or to force everyone to be more calorie conscious (mandatory restaurant menu labeling). In her opinion, the individual efforts of ordinary people to control their food intake and weight is ineffective. Obviously, if you’re a person who does this successfully, you’re going to disagree. It’s all about individuals. In fact, individuals can easily choose to ignore food portion restrictions or menu labels, so without a sense of individual motivation, all efforts at fighting obesity are going nowhere.
I admit to being surprised at how much she discounted exercise as a meaningful part of the solution. Clearly, exercise burns calories — just ask Michael Phelps. While most of us don’t have the time or motivation to burn 8000+ calories daily, we certainly can burn an extra 200 or 300 calories with physical activity, whether deliberately exercising or using our own muscles for transportation. That adds up to 1 lb lost every 12 to 18 days just with activity.
As for weighing as a means of monitoring weight, it works if you do it consistently and then act on the information. The main issue with scales and total body weight is that, unless you have a sophisticated scale, you don’t get information about body fat vs. lean body mass. Some people get frustrated if the number on the scale doesn’t go down, even though they’re losing body fat and gaining muscle mass. But clearly, if your weight starts creeping up a few pounds, you should cut back for a few days or ramp up the exercise. Monitoring can be achieved by daily calorie counting. If you’re very serious about your weight, you may do both.